A semiconductor memory device stores data using semiconductor elements. Semiconductor memory devices may be volatile memory devices, such as a DRAM and an SRAM and the like, or nonvolatile memory devices, such as an EEPROM, an FRAM, a PRAM, an MRAM, a flash memory, and the like. While a volatile memory device may lose data stored therein when the device is powered off, a nonvolatile memory device may retain data stored therein even when powered off.
In recent years, the integration degree of semiconductor memory devices has been improved with development of semiconductor integration technology. Thus, the capacity of the semiconductor memory device may increase. In particular, a flash memory system may be widely used as a storage medium of a computing system by virtue of merits such as a fast programming speed, a mass storage capacity, and the like.
To improve the capacity and operating speed of the flash memory system, a plurality of flash memory devices may be used. In this case, a power exceeding an allowable power of a power supply device of a host connected with a flash memory device may be used. This may mean that a power of the host and the flash memory device becomes unstable. An operation of the flash memory device may be limited by the unstable power. Thus, the performance of the flash memory system may be decreased.